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Density functional theory-based characterization of crystalline tungsten oxide has been well established. Nonetheless, there remains a partial gap in theoretical studies concerning the electrochemical characterization of amorphous tungsten oxide. The electronic structure and diffusion kinetics of amorphous tungsten oxide require a systematic theoretical study. Therefore, we employed second-generation Car–Parrinello molecular dynamics simulations and the density functional theory with HSE06 exchange–correlation hybrid functional to investigate the electronic properties and lithium kinetics of amorphous tungsten oxide (α-WOx, x = 3, 2.5, 2) models. The precise electronic properties of these structures were computed using the HSE06 hybrid functions. The diffusion properties of lithium were determined in the range of 1 × 10−7 to 5 × 10−7 cm2/s by ab initio molecular dynamics. The computational findings provide a critical atomic-scale understanding and contribute to the development of tungsten oxide-based electrochromic devices for practical applications. [ABSTRACT FROM AUTHOR]

Light field cameras are unsuitable for further acquisition of high-quality images due to their small depth of field, insufficient spatial resolution, and poor imaging quality. To address these issues, we proposed a novel four-focal-square microlens and light field system. A square aspheric microlens array with four orthogonal focal lengths was designed, in which the aperture of a single lens was 100 μm. The square arrangement improves pixel utilization, the four focal lengths increase the depth of field, and the aspheric improves image quality. The simulations demonstrate pixel utilization rates exceeding 90%, depth-of-field ranges 6.57 times that of a single focal length, and image quality is significantly improved. We have provided a potential solution for improving the depth of field and image quality of the light field imaging system. [ABSTRACT FROM AUTHOR]

Osteoarthritis (OA) is one of the most prevalent musculoskeletal diseases globally, leading to chronic disability and poor prognosis. One of the approaches for optimizing OA treatment is to find early effective diagnostic biomarkers. The contribution of microRNAs (miRNAs) in OA progression is now being increasingly recognized. This review provides a comprehensive summary on studies reporting the expression profiling of miRNAs in OA and associated signaling pathways. We performed a systematic search of the Embase, Web of Science, PubMed, and Cochrane library databases. This systematic review is reported according to the PRISMA checklist. Studies which identified miRNAs with aberrant expression compared to controls during OA progression were included, and a meta-analysis was performed. Results from the random effects model were provided as log10 odds ratios (logORs) and 95% confidence intervals. Sensitivity analysis was conducted to confirm the accuracy of the results. Subgroup analysis was conducted based on tissue source. The target genes of miRNAs identified in this study were extracted from the MiRWalk database, and these target genes were enriched in Gene Ontology and Kyoto Encyclopedia of Genes and Genomes pathways. A total of 191 studies reporting 162 miRNAs were included in our meta-analysis. Among them, 36 miRNAs distributed across 96 studies were expressed in the same direction in at least two studies (13 up-regulated and 23 down-regulated). Subgroup analysis of tissue source revealed that the highest number of studies was conducted using articular cartilage, where the most up-regulated miRNAs were miR-146a-5p (logOR 7.355; P < 0.001) and miR-34a-5p (logOR 6.955; P < 0.001), and the most down-regulated miRNAs were miR-127-5p (logOR 6.586; P < 0.001) and miR-140-5p (logOR 6.373; P < 0.001). Enrichment analysis of 752 downstream target genes of all identified miRNAs was performed, and the regulatory relationships among them were displayed. Mesenchymal stem cells and transforming growth factor-β were found to be the most important downstream effectors regulated by miRNA in OA. This study highlighted the importance of miRNA signaling in OA progression and identified a number of prominent miRNAs including miR-146a-5p, miR-34a-5p, miR-127-5p, and miR-140-5p which might be considered as potential biomarkers for OA. [ABSTRACT FROM AUTHOR]

Simple Summary: Various physiological activities of organisms, including movement, feeding, reproduction, breathing, excretion, etc., all require the participation of their neuromuscular systems. Echinoderms, a phylum closely related to chordates, possess a well-differentiated but simpler muscular system, which provides a great opportunity to trace the evolutionary origins of the vertebrate muscular system. Here, we review the morphology of different musculatures and the effects of different neurotransmitters and neuropeptides involved in muscle regulation in echinoderms. In addition, we highlight the potential molecular mechanisms underpinning the action of these chemical messengers on echinoderm muscles. The muscular systems of echinoderms play important roles in various physiological and behavioral processes, including feeding, reproduction, movement, respiration, and excretion. Like vertebrates, echinoderm muscle systems can be subdivided into two major divisions, somatic and visceral musculature. The former usually has a myoepithelial organization, while the latter contains muscle bundles formed by the aggregation of myocytes. Neurons and their processes are also detected between these myoepithelial cells and myocytes, which are capable of releasing a variety of neurotransmitters and neuropeptides to regulate muscle activity. Although many studies have reported the pharmacological effects of these chemical messengers on various muscles of echinoderms, there has been limited research on their receptors and their signaling pathways. The muscle physiology of echinoderms is similar to that of chordates, both of which have the deuterostome mode of development. Studies of muscle regulation in echinoderms can provide new insights into the evolution of myoregulatory systems in deuterostomes. [ABSTRACT FROM AUTHOR]

Vasopressin/oxytocin (VP/OT)-type neuropeptide is an ancient neurophysin-associated neuropeptide and has been intensively studied to be involved in multiple physiological processes in protostomian and deuterostome vertebrates. However, little is known about the functions of VP/OT-type neuropeptide in deuterostome invertebrates especially in echinoderms. Here, we firstly report VP/OT-type neuropeptide signaling in an important economic species, Apostichopus japonicus, which is widely cultured in Asia, with high nutritional and medicinal values. Molecular characterization analysis of holotocin and its precursor revealed the highly conserved features of VP/OT family. The candidate receptor for holotocin (AjHOR) was confirmed to be able to activate the signaling via cAMP-PKA and possible Ca2+-PKC pathway, and further activated the downstream ERK1/2 cascade. Holotocin precursor expression profile showed that they were mainly concentrated in circumoral nerve ring. Furthermore, in vitro pharmacological experiments demonstrated that holotocin caused contractile responses in preparations from A. japonicus. And in vivo functional studies indicated that short-term injection of holotocin resulted in body bloat and long-term injection resulted in reduced body mass, suggesting potential roles of holotocin in osmoregulation and feeding co-inhibition with holotocin–CCK. Our findings provided a comprehensive description of AjHOR–holotocin signaling, revealed ancient roles of holotocin in osmoregulation and feeding inhibition by controlling muscle contractions. [ABSTRACT FROM AUTHOR]

In this paper, a pitching airfoil near flat and wavy ground is studied by numerical simulations. The kinematic features of the airfoil and the flow field around it are analyzed to reveal unsteady vorticity dynamics of the self-propelled airfoil in ground effect. The optimal pitching periods at different initial heights above flat ground are obtained, which make the pitching airfoil achieve the maximum lift-to-drag ratio. Compared with flat ground, at the same initial height, the optimal pitching periods vary with the shape of ground. The structure and the strength of the wake vortices shedding from the airfoil are adjusted by the wavelength of ground. This leads to the changes of amplitude and occurrence times of the peak and valley of lift and drag force. The results obtained in this study can provide some inspiration for the design of underwater vehicles in the ground effect. [ABSTRACT FROM AUTHOR]

TiCN-Ni based cermets were prepared by pre-solid solubilizing Ti in Ni to adjust the composition of the binder in advance. The composition, morphology, microstructure and effects on TiCN cermets of Ni-Ti powder were tested and analyzed by XRD, SEM, EDS and TEM. The mechanical properties such as transverse rupture strength, fracture toughness and hardness were tested. The results showed that the wettability of Ni to ceramic particles can be improved, and the particles could be refined by pre-solution treatment. The reasons for the improvement of wettability were as follows: the content of alloy elements in the binder phase during sintering was adjusted, the complete and uniform rim-shaped phase was formed, and a nanometer thickness transition zone was formed between the metal binder phase and the rim-shaped phase. In addition, a high density of dislocation in the transition zone could inhibit grain growth. The fracture mode of cermets was mixed fracture mode composed of intergranular fracture and transgranular fracture. When 3 wt.% Ti was fore-solid solubilized in Ni, the performance of the cermets was the best. The transverse rupture strength, fracture toughness and the hardness of the cermets reached 2356.8 Mpa, 14.33 MPa·m1/2 and 88.9 HRA, respectively. [ABSTRACT FROM AUTHOR]

Simple Summary: Pentamerous radial symmetrical echinoderm adults develop from bilaterally symmetrical larvae and are a great model for understanding the origin and evolution of deuterostome nervous systems. Neuropeptides are important neuronal signaling molecules that regulate diverse behavioral and physiological processes in animals including echinoderms. In this study, we revealed the remarkable complexity of embryonic and larval nervous systems, identified the neuropeptide profile, and quantified the expressions of specific neuropeptide precursor genes in Apostichopus japonicus embryo and larvae. Collectively, this research will enable us to have a more comprehensive understanding of the holothuroid embryonic and larval nervous system and gain insights into the potential functions of neuropeptidergic systems in holothuroid larvae. Here, we described the complex nervous system at five early developmental stages (blastula, gastrula, auricularia, doliolaria and pentactula) of a holothurian species with highly economic value, Apostichopus japonicus. The results revealed that the nervous system of embryos and larvae is mainly distributed in the anterior apical region, ciliary bands or rings, and the feeding and attachment organs, and that serotonergic immunoreactivity was not observed until the embryo developed into the late gastrula; these are evolutionarily conserved features of echinoderm, hemichordate and protostome larvae. Furthermore, based on available transcriptome data, we reported the neuropeptide precursors profile at different embryonic and larval developmental stages. This analysis showed that 40 neuropeptide precursors present in adult sea cucumbers were also identified at different developmental stages of embryos and larvae, and only four neuropeptide precursors (SWYG precursor 2, GYWKDLDNYVKAHKT precursor, Neuropeptide precursor 14-like precursor, GLRFAmprecursor-like precursor) predicted in adults were absent in embryos and larvae. Combining the quantitative expression of ten specific neuropeptide precursor genes (NPs) by qRT-PCR, we revealed the potential important roles of neuropeptides in embryo development, feeding and attachment in A. japonicus larvae. In conclusion, this work provides novel perspectives on the diverse physiological functions of neuropeptides and contributes to understanding the evolution of neuropeptidergic systems in echinoderm embryos and larvae. [ABSTRACT FROM AUTHOR]

Unmanned aerial vehicle remote sensing image matching techniques are crucial for urban planning and environmental monitoring. However, existing feature matching methods have limitations due to the lack of effective extraction of key diverse features, which hinders the improvement of matching accuracy for diverse ground scenes. To address the above limitations, we propose a remote sensing image feature-matching method using optimally regularized nonlinear diffusion model. Specifically, we first use the accelerated-KAZE (AKAZE) algorithm framework to detect and characterize features within a nonlinear scale space. To improve the adaptation of diffusion to the local image structure, we propose the introduction of a novel Charbonnier regularized nonlinear diffusion model for constructing the diffusion coefficients. We then propose to combine Brute force with the K -nearest neighbor algorithm to eliminate invalid matches. Lastly, we modified the sampling approach of the random sample consensus (RANSAC) algorithm. Instead, we achieve iterative dataset purification using the progressive sample consensus algorithm, complemented by the implementation of a termination criterion for the sampling process. Experimental results show that our method achieves an average matching precision of 82.8%, 80.2%, 82.9%, and 91.2% when the test set undergoes scale, rotation angle, noise blurring, and luminance variations, respectively, outperforming the existing feature matching methods. [ABSTRACT FROM AUTHOR]

This paper proposes that Ca2+ in steel slag (SS) has a weak early hydration activity when SS and granulated blast-furnace slag (GBFS) are used as alkali-activated cementitious materials. Herein, alkaline activators and Ca(OH)2 are used as indicators of Ca2+ reaction in the SS and GBFS system. It is found that the 28-day compressive strength of the cementitious material with 2 wt% Ca(OH)2 addition increased by 25.9% compared with the blank. Hydration products and microstructures were characterized by XRD, SEM/EDS, FTIR and TG/DTA. Results show that the addition of Ca(OH)2 increased the content of active calcium ions in the reaction system, which promotes the reaction and the formation of C–S–H gel, resulting in an enhanced compressive strength ultimately. It can be also concluded that SS is not suitable as a sole precursor for the production of building materials on a large scale due to the weak early activity of Ca2+ in SS. [ABSTRACT FROM AUTHOR]

In recent years, metal ceramic heaters (MCHs) have become widely used in daily life and industrial applications. This paper introduces a method for producing an MCH with high bonding strength of the bonding wires by adding oxide additives (Al2O3, SiO2, and MgO) to a metal slurry. Pilot experiments were carried out at 1600°C under a protective atmosphere. The results indicate that the temperature coefficient of resistance of the samples decreases whereas the bonding strength vastly increases, and the pulling forces of the bonding wires in the samples extends from 2 to 32 N. The pulling forces are progressively increased as the content of the spinel phase in the oxide additives increases. The mechanism of enhancement of the bonding strength is discussed herein. The microstructure characterization, element mapping, and element analysis of different samples were performed using a scanning electron microscope (SEM). The results indicate that the formation of a W‐Si solid solution in the sample is the main reason for the decrease in temperature coefficient of resistance. The interface between the metal and spinel layers forms a zigzag and interlocked shape, which significantly improves the bonding strength between the lead wires and the ceramic matrix of the MCH. [ABSTRACT FROM AUTHOR]

To study the deterioration law of mechanical properties of glass fiber reinforced composite (GFRP) bars in an alkaline solution, tensile tests were carried out using 20 mm and 25 mm GFRP bars for 30 days, 90 days and 180 days to obtain the mechanical properties such as ultimate tensile strength and elastic modulus after different corrosion time in the alkaline solution were obtained. Meanwhile, a comparative study on the mechanical properties of GFRP bars with the same diameters was conducted in saline solution for 180 days. The residual tensile strength degradation model was established for the GFRP bars in the alkaline solution. The results indicated that the deterioration degree of mechanical properties of GFRP bars in the alkaline solution was worse than that in the saline solution at the same corrosion age. The tensile strength of GFRP bars tended to decrease with an increase of soaking time in the alkaline solution, and their corrosion rate in the early stage was faster than that in the later stage. The modified residual strength degradation model of GFRP bars was in a good agreement with the test results. [ABSTRACT FROM AUTHOR]

High density of thermally stable Y-Si-O nanoparticles dispersed in the Fe matrix play a primary role in oxide dispersion strengthened (ODS) steel. In this study, the binding energies of solutes Y, O and Si with vacancies have been calculated in the framework of first-principles density functional theory. According to the calculations, any two solutes of Y, O and Si bound with each other strongly in the second nearest neighboring (NN) sites while not in 1NN. A vacancy (v) bounds strongly with Y and O in 1NN site. The binding sequence of solutes with v followed O-v → Y-v → Si-v, and the affinity of Y, Si and v with O followed O-Y → O-v → O-Si. The nucleation mechanism of Y-O-Si nanoclusters was determined, which gave the feasibility of adding Si to ODS steels. The core (consisting of Si and O)-shell (enriched Fe and Cr) structure of the microparticles was found in ODS steels containing Si, fabricated by mechanical alloying (MA) and vacuum sintering. Moreover the nanoparticles of monoclinic cubic Y2O3, Y2SiO5 and Y2Si2O7 with sizes of 5~12 nm were observed in ODS steel. Si reduced the sintering temperature by maximizing densities and mechanical properties at a lower sintering temperature. The steel with 3 wt% Si was sintered at 1280 °C, exhibiting the best comprehensive mechanical properties. The tensile strength, hardness and relative density were 1025 MPa, 442.44 HV and 95.3%, respectively. [ABSTRACT FROM AUTHOR]

The combination of conventional and advanced water treatment is now widely used in drinking water treatment. However, membrane fouling is still the main obstacle to extend its application. In this study, the impact of the combination of coagulation and ultrafiltration (UF) membrane rotation on both fouling control and organic removal of macro (sodium alginate, SA) and micro organic matters (tannic acid, TA) was studied comprehensively to evaluate its applicability in drinking water treatment. The results indicated that membrane rotation could generate shear stress and vortex, thus effectively reducing membrane fouling of both SA and TA solutions, especially for macro SA organics. With additional coagulation, the membrane fouling could be further reduced through the aggregation of mediate and macro organic substances into flocs and elimination by membrane retention. For example, with the membrane rotation speed of 60 r/min, the permeate flux increased by 90% and the organic removal by 35% in SA solution, with 40 mg/L coagulant dosage, with an additional 70% increase of flux and 5% increment of organic removal to 80% obtained. However, too much shear stress could intensify the potential of fiber breakage at the potting, destroying the flocs and resulting in the reduction of permeate flux and deterioration of effluent quality. Finally, the combination of coagulation and membrane rotation would lead to the shaking of the cake layer, which is beneficial for fouling mitigation and prolongation of membrane filtration lifetime. This study provides useful information on applying the combined process of conventional coagulation and the hydrodynamic shear force for drinking water treatment, which can be further explored in the future. [ABSTRACT FROM AUTHOR]

Preparation of LiCoO2 cathode materials from spent lithium–ion batteries are presented. It started with the reclaim/recycle of metal values from spent lithium–ion batteries, which involves the separation of electrode materials by ultrasonic treatment, acid dissolution, precipitation of cobalt and lithium, followed by the preparation of LiCoO2 cathode materials. Co (99.4%) and Li (94.5%) were recovered from spent lithium–ion batteries. The LiCoO2 cathode materials prepared from the reclaimed cobalt and lithium compounds showed good elecrtochemical performance. The reclaiming of cobalt and lithium has a promising outlook for the recycling of cobalt and lithium from spent Li–ion batteries, thus reducing the cost of Li–ion batteries. [ABSTRACT FROM AUTHOR]

Friction stir welding was carried out on AA6061/AZ31B alloy, and the influence of tool offset on microstructures and mechanical properties of the joints was studied. The results showed that preferred properties were obtained when Mg was placed in the Advancing Side (AS) and offset was positioned into Mg. The distribution of Al3Mg2 and Al12Mg17 intermetallic compounds (IMCs) could be improved with offset in a certain range. The tensile strength of the joints was elevated with the increase of the offset due to the superior distribution and diminished size of IMCs, and when the offset was 1.5 mm, the joint strength reached the maximum value of 107 MPa. The microhardness of the stirring zone decreased with the increased offset. [ABSTRACT FROM AUTHOR]